early-onset Lafora body disease
Findings
No curated finding names early-onset Lafora body disease yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Early-onset Lafora body disease is an extremely rare, inherited form of progressive myoclonic epilepsy characterized by progressive myoclonus epilepsy and Lafora bodies, with an early onset (at around 5 years) and a prolonged disease course. Other manifestations include progressive dysarthria, ataxia, cognitive decline, psychosis, dementia, spasticity, dysarthria, myoclonus, and ataxia. The disease course typically extends for several decades.
Definition from the Mondo Disease Ontology (MONDO:0014717), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal recessive inheritance
HPO, annotations 2026-09-02
Features
19 features
What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.
- Lafora bodiesHPOHP:0100318
- Very frequent (80% to 99% of cases)
- MyoclonusHPOHP:0001336
- Very frequent (80% to 99% of cases)
- Atypical behaviorHPOHP:0000708
- Frequent (30% to 79% of cases)
- DysarthriaHPOHP:0001260
- Frequent (30% to 79% of cases)
- HyperreflexiaHPOHP:0001347
- Frequent (30% to 79% of cases)
- AtaxiaHPOHP:0001251
- Occasional (5% to 29% of cases)
- ConfusionHPO
Show the remaining 7
- Generalized myoclonic seizureHPOHP:0002123
- HallucinationsHPOHP:0000738
- Progressive cerebellar ataxiaHPOHP:0002073
- Spastic ataxiaHPOHP:0002497
- Spastic tetraplegiaHPOHP:0002510
- SpasticityHPOHP:0001257
- Urinary incontinenceHPOHP:0000020
Genes
1 gene
Germline variants in the gene encoding each protein, as classified by GenCC submitters, each in their own words. Limited, disputed and refuted submissions are listed too.
- PRDM8HGNC:13993
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal recessive · 2018
- Supportive · Orphanet · Autosomal recessive · 2021
- Limited · PanelApp Australia · Autosomal recessive · 2025
Where it sits
- A kind of
Other names
3 names
Resolves to: early-onset Lafora body disease
- Also called
- epilepsy, progressive myoclonic, 10epilepsy, progressive myoclonic, type 10EPM10